best colorless pokemon cards List of All Type Special Energy Pokemon TCG : Double Colorless

Adding in a mass removal spell to a card draw one makes this very powerful at most kitchen table formats, and it's one color, so it's pretty easy to add into your decks in Commander where color identity matters

Additional copies of Swords to Plowshares, Chain Lightning, Preacher, King Suleiman, Spinal Villain, and Pyrotechnics are all worthy countertactics

Whenever one or more creature cards leave your graveyard, create a 2/2 black Skeleton Pirate creature token

One of the major drawbacks to doing a sixth color is that we fear that we'll be committed afterwards, because players will have decks based around that color and won't be thrilled by the idea that they won't be receiving any new cards any time soon